Collision of a stationary ball with a moving ball

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The discussion revolves around a physics problem involving two identical balls, where one ball (M) collides with a stationary ball (S). The momentum conservation equations are established, leading to two key equations that relate the initial and final velocities of both balls. The derived values show that the final velocities of both balls can be expressed in terms of the initial speed of ball M, confirming that the collision scenario is valid for any initial speed. The conclusion is that the relationship between the scalars demonstrates the feasibility of the collision outcome regardless of the initial conditions. This analysis effectively proves the problem statement.
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Homework Statement



Two identical balls (same mass and material) , of which the first one (named ball "M") moving in the direction = 3i + 4j collides with the second ball (named ball "S") which is stationary. After the impact, the ball "M" moves in the direction= 3i + 16j while ball "S"
moves in the direction = i.

Show that this can happen whatever the initial speed of "M" .

Homework Equations



P(after impact) = P(before impact) (where P denotes the vector quantity momentum)

law of restitution.

The Attempt at a Solution



U shows Initial velocity

let U(of M) be = n( 3i + 4j ) [where n= any "scalar" ,thus showing initial velocity]
let U(of S) be = k (oi+0j) = 0

V shows final velocity

let V(of M) be = c( 3i + 16j ) [again "c" is a scalar]
let V(of S) be = d( i ) [because the impulse and force act horizontally]


The velocity in j direction remains constant, while momentum is conserved in the x direction.

so i got two equations :
1) 3n = 3c + d [from conservation of momentum in i direction]
2) 4n = 16c ⇔ n/c = 4 [velocity remains unchanged in j direction]

I don't know what to do next, how do i prove this ?
 
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Can you resolve the equations to obtain c and d expressed in terms of n? If yes, what does that mean?
 
voko said:
Can you resolve the equations to obtain c and d expressed in terms of n? If yes, what does that mean?

Certainly,

c=n/4

and d= 9n/4

It means that for any value of "n" there is a value of "c" and "d" .

I don't see how this helps me .
 
That proves what you are supposed to prove.
 
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